575.2 323 



583.111 



V. 



Numerical Variation of Parts in Ranunculus 



repens. 



THE following paper was submitted to us by a friend, not for 

 publication, but as an example of the kind of work that can be 

 done by one having only an elementary knowledge, but with his 

 energies turned into profitable channels. Considering the importance 

 now attached to the study of variation, none will deny that this 

 account of actual facts is a useful, though a small, contribution. The 

 writer is one who has but little time at his own disposal, and the most 

 limited facilities for the study of either natural history or science. 

 We have therefore obtained permission to publish this first essay of 

 his as an encouragement to others in a similar position. It would not, 

 perhaps, be altogether waste of time if series of Ranunculus repens from 

 other parts of the country were examined in the same way, and the 

 results compared with those of Mr. Pledge. At all events, both in 

 zoology and botany, there are abundant opportunities for those who 

 are not satisfied to remain " mere collectors." — Ed. Nat. Sci. 



The 500 specimens examined were kindly supplied by Miss K. M. 

 Hall, curator of Whitechapel Public Museum, since my occupation 

 prevented me from collecting them myself. They were all obtained 

 from one locality. It may be interesting to note that the sum-total of 

 all the parts counted, viz., the sepals, petals, stamens, and carpels of 

 500 specimens, amounted to 50,642, averaging over 100 pieces to each 

 specimen tabulated. 



The method employed in the investigation was as follows : — Four 

 separate sheets of square-ruled paper were used, one sheet for sepals, 

 one for petals, and one each for stamens and carpels. Each specimen 

 done was numbered, the number being the same on all four sheets, 

 thus rendering it easy to ascertain the particulars of the variation in 

 each whcrl of any given specimen. 



The floral formula, calculated from the data obtained, is : — 

 Sepals, 5-004 ; Petals, 5-672 ; Stamens, 54-534 ; Carpels, 36-074. 

 Taking it as 5, 5, 54, and 36 respectively, not one specimen in the 

 whole 500 conforms to it. If taken as 5, 6, 55, and 36, however, there 

 is one specimen (No. 433) in agreement. So that practically the 

 formula thus obtained is purely a mathematical conception and has no 

 real existence. 



Sepals. — Fig. i shows the variation in the Calyx, each dot 

 representing 10 individuals. The actual numbers are : — 



2 A 2 



